Lubricant



Patented Sept. 28, 1943 LUBRICANT Carl F. Prutton, Cleveland Heights, Ohio, assignor to The Lubri-Zol Corporation, Wickliife, Ohio, a corporation of Ohio No Drawing. Application November 25, 1940, Serial No. 367,031

21 Claims.

This invention relates, as indicated, to lubricating compositions and more particularly to lubricating compositions which are predominantly hydrocarbon oil, the properties of which affecting its use for particular purposes are improved by the addition of materials which are particularly effective in rendering the lubricants suitable for use under conditions of extreme stress as imposed by high temperatures, high loads, etc.

In my co-pending applications, Ser. No. 737,070, filed July 26, 1934, 216,153, filed June 27, 1938 and 245,226, filed December 12, 1938, I have dis-' closed a broad class of lubricating compositions of general utility, particularly in the field of use where extreme pressures are encountered.

My present invention relates to the discovery that a certain class of such materials is particularly suitable for use in lubricants subjected to conditions of extreme stress such as those involved in the lubrication of heavily loaded gears,

and in the lubrication of internal combustion engines operating under severe service conditions; for example, those encountered by internal combustion engines particularly of the aviation and Diesel types.

It is the principal object of my invention, therefore, to provide a lubricating composition which is especially suited for the purposes described.

Other objects of my invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims; the following description setting forth in detail certain approved combination of ingredients embodying my invention, such disclosed combinations of ingredients embodying my invention, such disclosed means constituting, however, but one of various forms in which the principle of the invention may be used.

Broadly stated, this invention comprises the provision of a lubricating composition for the purposes specified, characterized by the fact that the same contains a lubricating oil, preferably of the hydrocarbon type, as a major constituent with the properties of such composition afiecting its use as a lubricant, especially under the conditions specified, by the incorporation therein of a minor amount, based on the amount of lubrieating oil present, of a stable, oil-soluble salt of an aromatic acid.

More especially, my invention comprises the discovery that salts of aromatic acids, of the type which contain a substituent selected from the class consisting of aliphatic and cyclo-aliphatic radicles, are particularly suited for use.

The oil base The oil base of my lubricating compositions is a lubricating oil of the type best suited for the particular use for which the ultimate composition is designed. When the lubricating compositions of my invention are designed for the lubrication of automobiles, the oil ,base will of course preferably consist of a refined. mineral lu- 0 well known constituents such as those which improve the oiliness, film strength, pour point, cold test, corrosiveness, and oxidation properties, etc., of the oil. In general, composition of my invention may be employed with any commercially available addition agents for the above defined purposes since they are generally compatible with the same in the amounts usually used.

The addition agents As above indicated, the addition agents may be generally defined as salts of aromatic acids. The term salts as used herein is intended to include the salts formed by organic bases with aromatic acids as well as the salts formed by inorganic bases with aromatic acids. The inorganic base salts such as the metallic salts of aromatic acids will generally be found to give best results, and of these, those salts in which the metal is present in polyvalent and especially in divalent form, will usually be preferred. 5

The halogen bearing salts of aromatic acids generally are a broad class of addition agents which have been found to be notably efiective.

For certain uses, the salts of aromatic acids of the tye which contain a substituent selected from the class consisting of aliphatic radicles and cycle-aliphatic radicles have been found very useful. This latter class of salts may optionally also contain a halogen such as chlorine.

Due to the nature of the addition agents contemplated for use, they may be conveniently identified by firsthaving reference to the various aromatic acids from which the salts may be prepared and bythen giving a list of the various radicles or bases which may be combined with such acids in producing the salts.

TABLE I.AROMATIC Acms A. Aromatic acids with carbonyl group attached to ring Benzoic acid Benzcic acid derivatives:

Hydroxybcnzoic acids p-Hydroxybcnzoic acid Salicylic acid iclyhydroxybenz oic acids Protocatechuic acid Pyrocatcchuic acid Rcsorcylic acids Gallic acid Toluic acids Xyiic acids 'Irlmcthyl benzcic acids Ethyl benzoic acids Lauryl benzoic acids Cetyl benzoic acids Cyclo- Carnaubyl benzoic acids (J eryl benzoic acids Montanyl benzoic acids Myricyl benzoic acids aliphatic substituted benmic acids Cyclohaxyl-banzoic acid Methyl-cyclohexyl benzolc acids Amyl-cyclohexyl benzoic acids Naphthenyl-benzoic acids N aphthenoyi benzoic acids Ether-substituted benzoic acids Methoxy-benzoic acids Ethoxy-benzoic acids Lauroxy-benzoic acids Phenoxy-benzoic acids ratric acid Piperonylic acid Kate-substituted benzoic acids Acetyl bcnzoic acids Lauroyl benzoic acids Stearoyi bcnzoic acids Naphthenoyl benzoic acids nzoyl benzoic acids Ester-substituted benzoic acids Monoesters i phthalic acid,

Isophthalic acid and tereph- (R0 0 CC H4C O OH) thalic acid Mono-methyl phthalatc Mono-amyl phthalatc Mono-lauryl phthalatc Mono-benzyl phthalate Mono-cyclohexyl phthalate Amide-substituted bcnzoic acids Mono-amides oi phthalic acid, and

isophthalic acid, and tercph- R thalic acid RI NMethy1 phthalic acid mono-amide N-Amyl hthalic acid mono-amide N-Laury phthalic acid mono-amide N-Cyclohexyl phthalic acid mono-amide N-Methyl cyclohexyl acid mono-amide Thin-amide substituted benzoic acids Mono thin-amides of I phthalic acid, iso hthalic acid, and R terephth ic acid e. 3. where R and R are- Salicyl I Alkilated salicylic ac ds thyl sal Ant Methyl, amyl, lauryl; cyclohcxyl, methyl cyclohexyl,

etc. ic acid derivatives:

icylic acids Lauryl salicylic acids Cyclohexyl salicylic acids Naphthenyl salicylic acids Stearoyl salicylic acids hranilic acid derivatives:

With substituent in ring e. g.

Alkylated anthranilic acids Propyl anthran lic acids Amy anthranil c acids Lauryl anthramlic acids Phenyl authranilic acids Banzoyl anthran l c ac ds Stearoyl anthramlic acids Bydroxy-phenyl anthranilic acids (2) With substituent attached to nitrogen atom, e. g.

N -alkylated anthranillc aci s N-methyl anthranllic ids N-dimethyl anthrauilic acids N-arnyl anthranilic acids N-lanryl anthranilic acids N-dilauryl anthranilic acids N -ceryl anthranilic acids N-acetyl anthranilic acids N -stcaroyl anthranilic acids N -naphthenoyl anthranilic acids N-phenyi anthranilic acid N -diphen l anthranilic acid N -benzoy anthranilic acid N-naphthyl anthranilic acid Benzene pqlycarboxylic acids Ihthalic ac Isophthalic acid Terephthalic acid Benzene tricarboxylic acids Benzene tetracarboxylic acids Diphenyl carboxyllc acids Phenyl benzoic acids Diphenic acid Diphenyimethane carboxylic acids o-Benzyi benzoic acid Benzyl phthalic acids Bcnzophenone carboxylic acids o-Benzoyl benzcic acid Benzoyl phthalic acids Naphthalene carboxylic acids Aipha-na hthoic acid Beta-nap thoic acid Naphthalelnglfolycarboxylic acids N apht 0 acid Anthraoene carboxylic acids Anthraquinone carboxylic acids Phenanthrane carboxyllc acids Heterocyclic acids Furan carboxyllc acids Furoic acid (pyromucic acid) Pyrrole carboxylic acids Pyrrole alpha-carboxylic acid 'lhiophcne carboxylic acids Thiophene alpha-carboxylic acid Thiophene beta-carboxylic acid Pyridine carboxylic acids Picolinic acid Nicotinic acid Pyridine polycarboxylic acids Pyridine d i rbox glic acids Quininic acid Acridinic acid I B. Aromatic acids containing fatty-acid radicles having a plurality of carbon atoms Aromatic-acetic acids Phenyl acetic acid Diphenirl acetic acid Benzoy acetic acid XenyJl acetic acid N 821 thyl acetic acid S cyl acetic acid Aromatic propionlc acids Phenyl propionic acids Hydratropic acid Hydrocinnamic ac Benzoyl ropionic acid Dipheny propionic acid Xengl propionic acid Nap thyl pro ionic acid Furyl propio 0 acid Hydroxyphenyl propionic acids Hydrocoumanc acids Aromatic caproic acids Phenyl caproic acid Diphenyl caprclc acid Xengl ca r010 acid Nap thy caproic acid Tolyl caproic acid Xylyl caproic acid Aromatic caprylic acids Phenyl caprylic acid Naphthyl ca ryiic acid Xylyl capry 0 acid Aromatic capric acids Phenyi capric acid N aphthyl capnc acid Xy yl capric acid Aromatic lauric acids Phenyl lactic acid Lauryl-phenyl lauric acids Naphthyl lauric acid D. Aromatic acids other than carbomylic Hydroxyl-aontaining derivatives of benzene B. Aromatic acids containing fatty-acid radicles having a plurality of carbon atoms-Cont.

Pyrogallic acid Aromatic myristic acids Pyrogallic acid derivatives Phenyl myristic acid Alk lated yrogelllc acid N aphthyl myristic acid 5 afif m acid Aromatic palmitic acids E5159! 0f 8 0 acid 7 Phenyl palmitic acid Methyl allate N aphthyl palmitic acid Amy] a late Xcnyl palmitic acid Laury gallate 'Iolyl palmitic acid P1161171 Ballate Xylyl palmitic acid Benzyl gallate o-Hydroxyphenyl palmitic acid 10 g y e v 8811MB o-Benzoylphcnyl palmitic acid et yl-cyolohexyl-gallate Stearoyl-phenyl palmitic acid m ggific Aromatic stearic acids Game Mm f Pkenyl Swarm gcid- N-lauryl gallic acid amide l ifii h e y l s ii c rfi d HydmXyl-coifitaining derivatives of trlphenyl methane Xenyl stearic acid gg fifi g g Na hthyl stearic acid Mercaptoqosonc acid o-O yclohexyl-phenyl stearic acid Thimmsolic acids T1y1 Steam Bold Any oi the acids listed above under A, B, C, and D in which one Xylyl stearic acid Ethyl-phenyl stearic acid Lauryl-phenyl stearic acid Benzyl stearic acid Benzoyl stearic acid o-Hydroxy-phenyl steai'ic ac d p-Hydroxy-phenyl stearic acid Hydroxy-xenyl stearic acids Dihydroxy-phenyl stearrc acids Amino-phenyl stearic acids N-lauryl-amino-phenyl stearic acids N -cyclohexyl-amino-phenyl stearic acids N-dilauryl-atnino-phenyl stearic acids Salicyl stearic acids Benzoyl-phcnyl steai'ic ac ds Stearoyl-phenyl stearic ac ds Phenoxy-phenyl stearic ac ds Mcthoxy-phenyl stearic acids Lauroxy-phenyi stearic acids Furyl stearic acid Pyridyl stearic acid Phenyl hydroxystearie acid Phenyl glyoxylic acid Benzoyl glycolic acid Hippuric acid Phenyl glycine Phenyl glycine o-carboxylic acid Phenyl alanine Benzilic acid Phthalonic acid N -phenyl succinamic acid N-diphenyl succinamic acid Benzyl tartronic acid Aromatic unsaturated acids Atropi'c acid Cinnamic acid Coumaric acid Phenyl angelic acid Phenyl cinnamic 8 0ld Phenyl crotonic acid Phenyl-amino crotonic acid Phenyl propiolic acid Benzoyl acrylic acid Phenyl oleic acids Phenyl ricinoleic acid Benzal lactic acid Benzal malonic acid Fural malonic acid Benzal propionic acid C. Aromatic cycle-aliphatic acids Phenyl 2,3,4-triinethyl cyclopentane-3 carboxyllc acid Aromatic derivatives of cyclohexane carboxylic acids Phenyl hexa-hydrobenzoic acids Hydroxy-phenyl hexahydrobenzoic acids Benzyl hexahydrobenzoic acids Benzoyl hexahydrobenzoic acids N aphthyl hexahydrobenzoic acids Phenyl hexahydrophthalic acids Benzoyl hexahydrophthalie acids Hydroxy-phenyl hexahydrophthalic acids Phenyl quinic acid I or more oxygen atoms have been replaced with sulphur. Any of the foregoing which have been halogenated or in which one or more hydrogen atoms have been replaced with a halogen.

(l) Condensing an aromatic compound with (a) An aliphatic unsaturated acid, or (b) A halogenated aliphatic acid, or (c) A cyclo-aliphatic unsaturated acid, or ((5a) A halogenated cycle-aliphatic acid; or by (2) ondensing an aromatic acid with a) An unsaturated aiighatic compound, or

b) A halogenated alip atic compound, or

(0) An unsaturated cyclo-aliphatic compound, or (d) A haolgenated cycle-aliphatic compound.

Aromatic compounds which may be used in any of the condensation reactions identified under (1) above in the preparation of aromatic acids from which appropriate salts may be prepared are as follows:

TABLE H.ARoMATIc COMPOUNDS I. Hydrocarbons (A) Benzene and its homologs such as toluene, xylene, cymene,

ethyl-benzene, mesitylene. (B) Polyphenyls such as diphenyl, diphenyl benzene, and homologs of them such as o-phenyl toluene, poly-ethyl diphenyls, propyl diphenyl.

(C) Condensed ring hydrocarbons (l) Naphthalene and its homologs, such as the methyl naphthalenes, ethyl naphthalenes, propyl naphthaienes.

(2) Phenanthrene and anthracene and their hoinologs such as the monoand di-methyl, and propyl and iso-propyl, substitution products, e. g. retene.

(3) Chrysene and picene and their homologs.

(1) Compounds resulting from substitution of aryl groups in compounds oi classes (A), (B) and (C), e. g., di-benzyl, di-naphthyl, phenyl naphthalenes, the polyphenylmethanes e (E) Bridged ring hydrocarbons such as certain of the terpenes and related compounds including pinene, camphene and 5 limonene.

II. Heterocyclic compounds of the aromatic or allied type such as:

pyridine, quinoline, etc. and their derivatives.

IlI. Substitution products (other than hydrocarbon homologs) of compounds of classes I and II, including: (A) Oxygen-bearing sunstitution products. (See Table No.

Il(a) below, for iurther classification.) (B) Halogen-bearing substitution products.

(0) Other substitution products, such as those resulting from substitution oi the following groups:

Amino, and substituted Mercapto amino groups Sulphide Imino Polysulphide Azo Thiocyanate Hydrazo Isothiocyanate Hydrazine Dithiocarboxglic acids (al- Nitrile so ester an salt groups Isonitrile derived therefrom) IV. Derivatives of the compounds included in classes I II, and III resulting from addition reactions, such as hydrogenation, halogenation, etc. Examples of such compounds are the hydro-naphthalenes, phenyl cyclohexane, phenyl cyclohexanol, cyclohexyl phenol, naphthalene tetrachloride.

Attention is called to the fact that certain of the compounds may belong to more than one class; as, for example, the halogenated phenols which belong in class II[(A) and H103), orthe 4. halogenated amino phenols, class III(A), (B) and (C).

The oxygen-bearing aromatic compounds (class III(A)) of Table No. I are of particular importance, and are, therefore, classified in further detail according to the nature of the attachment of the oxygen to the molecule, viz:

TABLE 11(0) I. Directly attached to one or more carbon atoms, as in the case of:

(1') Ethers and analogous compounds (2') Compounds containing the -t-on radiclc, such as alcohols and other derivatives of carbinol (including phenols, cresols, naphthols, etc.) (3') C ompounds containing the carbonyl radicle, such as amides, aldehydes, ketones, organic acids, esters and salts of organic acids (including such salts of both inorganic and organic bases), tliio-acids and esters and salts of thio-acids. (4') Compounds in which oxygen ffl il5 a part of the ring structure, e. g. furan and its derivatives, etc. i (5') Compounds with an inorganic radicle where the oxygen 18 directly attached to a carbon atom, e. g. Arseni tes 'Ihiophosphites Hypochloritcs fi-Hydroxylamines Phosphites Borates 'lhiophosphates (N0tt.'lhis class includes salts of organic bases with inorganic oxy-acids.)

For specific examples of oxygen-bearing aromatic compounds, reference may be had to the table beginning on page 6 of my co-pending application Ser. No. 737,070, filed July 26, 1934. These examples include both the unhalogenated compounds listed and the halogenation prodnets of them.

The following is a list of aliphatic unsaturated acids which may be used as one of the components of the condensation reactions identified under (1) (a) above in the preparation of aromatic acids from which salts may be accordingly prepared.

TABLE III.ALIPHA'rIc UNSATURATED Acins l'Ilacostearie acid Propiolic acid Stearolic acid Vinyl acetic acid Vinyl acrylic acid Vinyl glycolic acid Acrylic acid Methyl acrylic Crotonic acid Beta pentnnoic acid Oleic acid Undecylenic Linolenic acid Myristolen e Malcic acid Palmitolenic Hydroxymaleic acid Acetylene dicarboxylic acid Fumaric acid Ilydrosorhic acid (llutaconic acid Sorhic acid Linoieic acid Ricinoleic acid TABLE IV.-HALOGENATED ALIPHATIC Acrns (hlorlactic acid (hlorsuccinic acid Chloradipie acid (lilorsuheric acid Chlorscbacic acid Ciiiormalic acid Clilortartaric acid Chlorcitric acid (hloracetie acid (lilorbutyric acid Chlorlauric acid Ciilormyristic acid Clilorpalniitic acid Chiorstearic acid Dichloroleic acid Chlor-ricinoleic acid Laurolenic acid Chlor-naphtiienic acids Chlor-ethylene-acetic acid Ohlorvinaconic acid Chlor-caronic acid Chlor-norpinic acid C-hlor-pinic acid Chlor-pinonic acid (hlor-truxiliic acid Chlot-cainphoric acid Chior-camphenie acid As well as the chlor derivatives oi all of the acids given in Table V;

In the following table are given representative examples of cycle-aliphatic unsaturated acids which may be used as one component of the condensation reaction identified under (1) (b) above.

TABLE V .--CYCLO-ALIPHATIC UNSATURATED ACIDS Methyl eyclohexylideiie acetic acid Chaulmoogric acid Hydrocarpic acid Furzil acrylic acid Tetrahydrobenzoic acid Fural malonie acid 'letrahydrophthaiio acid Beiizal malonic acid Dibydro hthalic acids Benzal propionic acid Tctrahy otoluic acids Benzal lactic acid Tetrahydrcylic acids Abietic acid In the following table are given certain repre- TABLE VI.HALOGENATED CYCLO-ALIPHATIC Acms Chlor-hexahydrcbenzoic acid Chlor-hexahydrobcnzoic piitliahe acid Chlor-quinic acid Chlor-decahydronaphthoic acids Chlor-camphenonie acid Chlor-cholanic acid Ciilor-clioiic acid Chlor-choleic acids When the second type of condensation reaction is employed, 1. e. that identified under (2) above; where an aromatic acid is condensed with an aliphatic compound, the aromatic acid may be any of the acids given in Table I above.

When the condensation reaction of the type identified under (2) (a) above is employed, the unsaturated aliphatic compounds, which may be used in such condensation reaction, may be any of those listed in the following table.

TABLE VII.UNSATURATED ALIPHATIC COMPOUNDS Hydrocarbons Decene Ethylene Acetylene Propylene Butadicue Butylene Allene lsohutylene Amylene Di-isobutylcne As well as those unsaturated products derived from petroleum and petroleum fractions and derivatives such as paratiin wnx as by cracking or for example removal of HCl by NaOH from moiinchior pamiiins. The unsaturated products derived from cracked gasoline, gas oil etc. will be iound particularly useful.

Unsaturated organic compounds other than Included Ttlble N 0. 1

(A) Oxygen-bearing substitution products (for further classification and examples see Tables Nos. 2 and 3 below).

(B) Halogen-bearing substitution products (0) Other substitution products such as those containing the following substituent groups:

Amino, and substituted amino Mercapto groups sulphide lmino Polysulphide Azo Thiocyanate Hydrozo Isothiocyanate liyd razine Dithiocarbcxylic acids (also Nltllle ester and salt groups derived lsonitrile therefrom) Nata-This invention contemplates the use of compounds containing more than one substituent group. In such cases the compound may belong in two or more of the above classes.

Examples of the oxygen-bearing compounds are as follows:

Table 2 flet rocy clig aaids including:

are c Pyrrolcarborylio acids 3iitlt$llitiiti 353115? mm Pwdlnewbowllmlds Allyl alcohol Crotonaldehyde' 1W add! w Crotonyl alcohol Hexadlenal ycullo-halogen acids Oleyl alcohol Octatrienal g Hogan acids Propargyl alcohol Citral fi 801d- Propargylio aldehyde T g g ig (3) Unsaturated ketones, e. g. Carbong Mid it Thiooarbonie was their 0213? fi osp orous ac rgiorone Thiophos horous acids nylleuryl ketone phospho 08cm Acetylenic ketones (e. g. R-CsC-C 0-H), such as: Tmophosphoflo acids Allylene methyl ketone Cyanic acid Allylene lauryl ketone Tmocyamc acid (39) Ketenes H dro anic acid Ketene r Bo rio a c id Acetyl ketene (7) Salts of unsaturated acids, including the (4) Unsaturated others, Ammonium and substituted ammonium i-vinyl ether sodium Di-allyl ether calcium Ally] ethyl ether Barium Vinyl ethyl ether can; Ally] iso-amyl ether Aluminum glyl lauriyltilalthlerth 2o ggg opargy e y e at Lead (5) gi g i gg g Salts of unsaturated acids generally, and more specifically of such we id acids as those listed under (5) above and of unsaturated arovinyl alcry l(:sc d matic acids. M 3115 551% c m In addition to the compounds listed above I gfg fgf commercial products comprising complex mix- I o eic g d tures of unsaturated oxygen-bearing organic fi'y d i' xymaleic acid compounds may be used as the unsaturated re- Furnaric acld actant. Examples of such materials are the fatty Glutaconic acid u f t t d h t le tfi r? idid O S 0 111159. ura 6 C 819:0 er, e. g.

Castor oil Linseed oil ggggg gggg Chinawood 011 Menhaden as: oil Acetylene dicarboxylic acid ggzag on g g gggg 8% fig gg ggg g gag Croton oil Sperm oil Itaconic anhydrlde Lard Citraconic anhydride 1 Additional material, for use as the unsat- Pymimhwim anhyd urated reactant in the condensation, may be de- Xeronic anhydrlde Glutaconic anhydride r1ved from any of the above fatty oils, e. g. Methyl glutsooulc anhydride Dimethyl anhydride (6) Unsaturated esters. e. g.

(a) Esters of unsaturated acids (e. g. those listed under (5) above as well as unsaturated aromatic acids such as cinnamic and coumaric) with monoand poly-hydric alcohols, or other hydroxy compounds (including phenols). Examples of such alcohols and hydroxy compounds are:

Methyl alcohol Ethyl alcohol Propyl alcohol Butyl alcohols Amyl alcohols Lauryl alcohols Cetyl alcohols Lyclohexanol Alkylated cyclohexanols, e. g. methyl cyclohexanol Benzyl alcohol Furiuryl alcohol 'letrahydrofurluryl alcoho Ethylene glycol Propylene glycol Di-ethylene glycol Glycerol Y Polyhydroxy-benzcnes Alkylated phenols Naphthols Unsaturated alcohols (c. g. those listed under (1) above) Esters of unsaturated alcohols (e. g. those listed under (1 above) with organic acids, either aliphatic or aromatic, or with inorganic acids. Examples of such acids are: Aliphatic acids, including:

Saturated acids, such as:

Acetic acid Propionlc acids Butyric acids Lauric acids Palmitic acid Stearic acid Oxalic acid Citric acid Lactic acid Glycolic acid Malonlc acid Tartaric acid Unsaturated acids, such as those listed under (5) above. Aromatic acids, including:

Benzoic acid Phthalic acids Salicylic acid Anthranilic acid Cinnamic acid Cyclo-aliphatic acids, including:

Naphthenic acids Bexahydrobanzoic acid the molecule, viz:

(1) Acids, extracted from the oils by direct hydrolysis, or by saponiflcation and subsequent hydrolysis, or otherwise.

(2) Esters, produced by esterilying the acids of l) e. g. to form esters analogous to any of those listed under (6 in Table No. 2.

(3) Soaps, reduced by saponifying the oils directly or by neutraliz: ing t e acids oi (1) with alkalies, e. g. to form salts analogous to those listed under (7) in Table No. 2.

The unsaturated oxygen compounds are of particular importance and may, therefore, be classified in further detail according to the nature'of the attachment of the oxygen atom to Table N0. 3

I. Directly attached to one or more carbon atoms, as in the case oi (1) Ethers and analogous compounds (2) Compounds containing the radicle, such as alcohol; and other derivatives of mrbinol (including phenols, cresols, naphthols, etc.) (3') Compounds containing the carbonyl radicle, such as amides, aldehydes ketones, organic acids, esters and salts of organic acids (including such salts of both inorganic and organic bases), thio-acids and esters and salts of thio-acids. (4') Compounds in which oxygen forms a art of a ring structure, e. g. compounds containing the fury or hydro-fury] groups. (5') Compounds with an inorganic radicle where the oxygen is directly attached to a carbon atom, e. g.

Perchlorate (N0l e.-This class includes salts of 'organic bases with inorganic cry-acids.)

In the following table are listed a number of representative halogenated aliphatic compounds which may be used as one of the components of the condensation reaction identified under (2) (l7) above.

TABLE VIII.HALOGENATED ALIPHATIC COMPOUNDS Eth lchloride Benz ichloride Butgl chloride Ethy ene dichloride Amyl chloride Carbon tetrachloride La 1 chloride Chlorpaiaflin wax Cet yfchloride Chlor naphtha Ceryl chloride Chlor decane Melissyl chloride Amyl dichloride Chi rinated all hatic raifin derivatives as well as the chlorinated d rivatives 1 the 53am materials and compounds listed in Table VII above.

In the following table are listed a number of specific examples of unsaturated cycle-aliphatic compounds which may be employed as components of the condensation reaction identified under (2) (c) above.

TABLE IX.UNSATURATED CYCLO-ALIPHATIC CoMPouNns Examples of such unsaturated cyclic compounds are:

' Terpineol Iso ulegol D ydrocarveol Pinocarveol Aldehydes Ketones Pulegone Piperitone Carvone Eucarvone Ionone Pinocarvone Verbenone Carvenone Ethers Pinol Tetrahydro-anisole 'letrahydiophenetole Acids Laurolenic acid Chaulmoogric acid Hydrocarpic acid Tetrahydrobenzoic acid Tetrahydrophthallc acid 'Ietrahydrotoluic acids Dihydrophthalic acids 'Ietrahydro-xylic acids Methyl cyclohexylidene acetic acid Fural acrylic acid Fural malonic acid Benzal malonic acid Benzal propionic acid Benzal lactic acid Abietic acid Commercial products comprising complex mixtures of unsaturated cyclic organic compounds may also be used, e. g.

Turpentine Pine oil In the following table are listed a number of representative examples of halogenated cycloone of the components of the condensation reaction identified under (2) (d) above.

TABLE X.Har.ooamran CYCLO-ALIPHATIC COMPOUNDS Halogenated c clo-aliphatic hydrocarbons Chlorcyclo utane Chlorcyclopentane Ghloreth icyclobutane Chlorcy ohexane Chlormeth lcyclohexane Dichlorcyc ohexane Chlorcycloparaflin Dichloreyclo ntane Halogenated cyc o-alipbatic alcohols Chlorcyclo entanol v Chlorcyclo exanol Chlormethyicyclohexanol Chloramylcyclohexanol Chlorquinitol Chlormenthol Chlor-terpins Chlor-terpineols Chlor-borneol Halogenated cycle-aliphatic ketones Chlorcyclobutanone Chlorcyclobutyl methyl ketone Chlorcyclopentanone Chlor-cyclohexanone Chlorrnenthone Chlor-camphor Brom-camphor Halogenated cyclo-eli hatic esters Chlormethyl-nap thenates Chlorcyclohexyl-aoetate Chlorcyclohexyl-stearate Chlormethyl-hexahydrobenzoate Chlor dl-methyl-hexahydrophthalate The various aromatic acids, either those spe- 0 cifically identified in Table I above or those prepared by the various condensation reactions above identified, may, as previously indicated, be combined with either an organic radicle or base in the preparation of organic salts or with inorganic bases in the preparation of the inorganic salts.

In the following table will be found listed a number of organic radicles or bases which may thus be employed in the preparation of organic salts of aromatic acids.

TABLE XI.ORGANIC RADICLES 0a BASES Amino compounds such as: Quinaznlinc M onoethanolamiue Pyrollinc Diethanolamine Pyridazine 'lriethanolamine Picoline Aniline Pyrazolo Benzylamine Pyridine Laurylamine Quinoline Dipbenylaminc Pyrrole Triphenylaminc Piperidene Diethylemine 'lhiazole 'Iriethylamine ("arbazole Putrescine Pheuoxazinc Nitrogen ring compounds, such as: Phenthiazinc Pyrimidine lndole Pyrazine Indcxyl Phenazine 'lhiodiazcle Oxygen-bearing ring compounds, such as:

'y-Pyrone Among the specific organic salts of aromatic acids which may thus be prepared for use, may be listed the following as illustrative examples.

TABLE XIL-ORGANIC SALTS Aniline phenyl stearate Benzylamine chlnrphenylstearate Laurylamine naphthylstearate Diphenylamine chlornaphthylsteeratc Diethylamine phenylmercaptostearate Ethanolamine phenylpalmitate 'lriethanolamine piperidyl lauratc Pyridine phenyl stearate Quinoline naphthyl naimitate Piperidene chlor nap'dhyi lauratc Thiazole phenyl palmitate 'y-Pyrone phenyl stearate In the following table are listed a. number of inorganic radicles which may be combined with any of the aromatic acids given above in the production of inorganic salts of aromatic acids which may be used as addition agents in the lubrialiphatic compounds which may be employed as, eating compositions of my invention.

In the following table are given a list of representative inorganic salts which may be produced by the combination of certain of the aromatic acids above identified with certain of the inorganic radicles of Table XIII above.

TABLE XIV.INoRoANIc SALTS Calcium diphenyl acetate Magnesium diphenyl acetate Nickel diphenyl acetate Cobalt diphenyl acetate Stanuous diphenyl acetate Potassium phenyl stearate Ammonium phenyl stearate Lithium phenyl stearate Magnesium phenyl stearatc Calcium phenyl stearate Strontium phenyl stcarate Barium phenyl stearate Cobalt phenyl stearate Zinc pbenyl stcarate Nickel phcnyl stearate Manganese phenyl stearatc Aluminum pbenyl stearotc Chromium phenyl stcaratc Stannous phcnyl stearate.

Copper phenyl stcarate Cadmium phenyl stcarate Si.ver phenyl stearatc Vanadyl phenyl stearatc Calcium phenyl mercapto stearate Magnesium phenyl mercapto stcarato Nickel phenyl mercapto stearate Cobalt phenyl mercapto stearate Stannous phenyl mercapto stearatc Calcium xenyl stearate Magnesium xenyl stearato Nickel xenyl stearate Cobalt xenyl stearate Stannous xenyl stearatc Calcium naphthyl stearnte' Magnesium naphthyl stearatc Nickel naphthyl stearute Cobalt naphthyl stearate Stannous napbthyl stearatc Calcium tolyl stearate Magnesium tolyl stearate Nickel tolyl stearate Cobalt tolyl stearate Stannous tolyl stearate Magnesium butyl phthalate (salt-ester) Calcium butyl phthalate (salt-ester) Nickel butyl phthelate (salt-ester) Cobalt butyl phthalate (salt-ester) Aluminum butyl phthalate (salt-ester) Calcium decyl phthalate (salt-ester) Cobalt decyl phthalate (salt-ester) Nickel decyl phthalate (salt-ester) Stannous decyl phthalate (salt-ester) Calcium lauryl phthalate' (salt-ester) Cobalt lauryl phthalate (salt-ester) Nickel lauryl pbthalate (salt-ester) Stannous lauryl phthalate (salt-ester) Magnesium mercapto rcsolate Calcium mercapto rosolate Nickel mercapto rosolate Cobalt mercapto rosolate Aluminum mercapto rosolate Calcium lauryl rosolate The halogen-bearing salts corresponding to the foregoing halogen-free salts will be found of utility and the following are particularly useful:

Calcium chlor phenyl stearate Magnesium chlor phenyl stearate Calcium chlor naphthyl palmitate Stannous chlor phenyl palmitate Calcium chlorphenyl laurate Nickel chlor phenyl laurate Cobalt chlor phenyl lauratc Stannous chlor phony] lauratc Calcium chlor phenyl palmitatc Nickel chlor phenyl palmitate Cobalt chlor phenyl palmitatc Stannous chlor phenyl palmitate Calcium chlor phenyl myristate Nickel chlor phony] myristate Cobalt chlor phenyl myristate Stauuous chlor pheuyl myristate Calcium chlor naphthyl laurate Nickel chlor naphthyl laurate Cobalt chlor naphthyl laurate Stannous chlor naphthyl laurate Calcium chlor napbthyl palmitate Nickel chlor naphthyl palmltate Cobalt chlor naphthyl palmitate Stannous chlor narzlhthyl palmitate Calcium chlor nap thyl myristate Sodium chlor naphth lmyristate Nickel chlor naphthy myristate Cobalt chlor naphthyl myristate Stannous chlor naphthyl myristate Calcium chlor xenyl laurate Sodium chlor xenyl laurate Nickel chlor xenyl laurate Cobalt chlor xenyl laurate Stannous chlor xenyl laurate Calcium chlor xenyl palmltatc Sodium chlor xenyl palmitatc Nickel chlor xenyl palmi tate Cobalt chlor xenyl palmitatc Stannous chlor xenyl palmitate Calcium chlor xenyl myristate Sodium chlor xenyl myristate Nickel chlor xenyl myristate Cobalt chlor xenyl myristate Stannous chlor xenyl myristate Calcium chlor toluyl laurate Nickel chlor toluyl laurate Cobalt chlor toluyl laurate Stannous chlor toluyl leurate Calcium chlor toluyl palmitate Nickel chlor toluyl palmitate Cobalt chlor toluyl palmitate Stannous chlor toluyl palmitate Calcium chlor toluyl myristate Nickel chlor toluyl myristate Cobalt chlor toluyl myristate Stannous chlor toluyl myristate Calcium lauryl toluate Cobalt lauryl toluate Nickel lauryl toluate Stannous lauryl toluate Instead of preparing the salts designed for use as the addition agents of the present invention by treating any of the acids, of the type above identified, with an alkali for example such as sodium hydroxide in the preparation of the corresponding sodium salt of the acid, it is also possible to prepare corresponding salts by first preparing an ester of the acid, and then reacting such ester with an alkali such as sodium hydroxide to prepare, for example, the sodium soap of the acid, and then treating such soap with another salt in the preparation of a salt of a different inorganic radicle. Thus, for example, the methyl ester of chlorphenylstearic acid may be reacted with sodium hydroxide in the production of sodium chlorphenylstearate which is in turn reacted with calcium chloride in the production of calcium chlorphenyl stearate.

It may be preferable to prepare the ester, employed in the foregoing preparation of the salt, where such ester is one of an aromatic acid on page 2 above, by condensing an ester of an aromatic acid with an unsaturated compound or halogenated organic compound instead of condensing the aromatic acid itself with such compound. For example, in the preparation of salts of stearoyl benzoic acid, methyl benzoate may be condensed with stearoyl chloride to form methyl stearoyl benzoate, this ester saponified with sodium hydroxide, and the resulting sodium salt reacted with magnesium chloride in aqueous solution to form magnesium stearoyl benzoate. An example of the preparation of magnesium stearoyl benzoate in detail is as follows:

A mixture of 1 mole each of methyl benzoate and stearoyl chloride is dissolved in an equal weight of carbon bisulphide. One mole of anhydrous aluminum chloride is added slowly with the temperature at 45 C. and the mixture held at that temperature for one hour longer. The materials are then poured into a mixture of cracked ice and concentrated hydrochloric acid, and the carbon bisulphide layer removed and washed with warm water. Carbon bisulphide and moisture are then removed by distilling under vacuum leaving the condensation product, namely methyl stearoyl benzoate. The latter is saponified by adding 1 mole of sodium hydroxide in the form of a 10% aqueous solution, the mixture being refluxed until the aqueous solution is approximately neutral. One-half mole of magnesium chloride is added in the form of an aqueous solution which causes the precipitation of magnesium stearoyl benzoate. The water layer is decanted from the precipitate which is then dissolved in benzol and dried by removing the benzol and water by distilling under vacuum. The resulting product was dissolved in a naphthenic type all in a concentration of 1% and found to materially improve the oil when used in an internal combustion engine, particularly in preventing the formation of harmful deposits on the piston and piston rings.

Included among the compounds contemplated for use by this invention are stable oil soluble salt-esters of polybasic aromatic acids. These may be formed for example by neutralizing an acid ester of a polybasic aromatic acid with a base, or by partially saponifying a neutral ester of a polybasic aromatic acid with a base so that each molecule of the saponifled material retains at least one ester group in addition to at least one basic group.

Examples of such compounds are the saltesters of the following:

l. Benzene polycarboxylic acids, e. g.

Phthaiic acids Trimeslc acid 'lrimellitic acid Hemirnellitic acid Pyromellitic acid Mellophanic acid Prehnitic acid Benzene pentacarboxylic acid 2. Na hthalene polycarboxyiic acids, e. g.

aphthalic acids 3. Pyridine polycarboxylie acids, e. g.

utidinic acid Dipioolinic acid Cinchomeronlc acid Isocinchomeronic acid Dinicotinic acid Alpha-carbocinchomeronic acid Bcta-carbocinchomeronic acid Berberonic acid Trimesitinic acid Pyridine tetracarboxylic acids Pyridine pentacarboxylic acid Pyrrole polycarboxylic acids Quinoline polycarboxylicacids Thiophene polycarboxylic acids Thiazole Po ycarboxyiic acids Dipheny polycarboxylic acids, e. g. Diphcnic acid Dibenzyl polycarboxylic acids Anthracene polycarbcxylic acids Phenanthrene polycarboxylic acids Thiauthrene polycarboxylic acids Where such salt-esters are employed, it will generally be found advantageous to have at least one of the ester groups consist of an aliphatic or cycle-aliphatic group and preferably one containing four or more carbon atoms. For example, salts of the acid butyl or amyl esters of phthalic acid have been found suitable.

Specific examples of these salt-esters have been so labeled in the principal list of specific examples given above.

In view of the particular uses for which my compounded lubricants are intended, it is apparent that of the salts included in the foregoing enumeration of the addition agents which may be employed, those which are readily oil- Hi -d M OO porlgnunm soluble are the ones preferred for use. When these compounded oils are designed for use under conditions where high temperatures are usually encountered, the addition agents should be stable at elevated temperatures. For use in crankcase lubricants for internal combustion engines, they should preferably be stable to the extent where there will be substantially no decomposition, when the lubricating composition is exposed to temperatures up to 250 F.

The addition agents which are to be selected from the class described should be such that they are relatively non-corrosive with respect to the metallic surfaces with which they come in contact during use. Certain of the named addition agents may be found to be detrimentally corrosive to certain sensitive bearing metals, in which case an appropriate corrosion inhibitor may be employed in conjunction therewith in the composition,

A lubricating composition prepared in accordance with my invention and which is predominantly hydrocarbon oil may contain from an effective amount to 20% of the salt addition agent above identified, In general, it will be found that an amount as low as .l% will often be quite effective and that amounts in excess of 10% are seldom necessary. A preferred range of concentrations for the salt in the oil is from 25% to about 2%.

The principal use for which the lubricants of this invention are designed is in the crankcase of internal combustion engines. The oil base is therefore preferably a liquid highly refined mineral oil with the addition agent present therein in such amounts as not to detrimentally change the viscosity of the composition. The viscosity of the blended lubricant used for this purpose may vary from an S. A. E. 10 grade to an S. A. E. 50. Generally the blended lubricant in the viscosity range of S. A. E. 10, 20 and 30 will be found of most general utility.

It is also within the contemplation of this invention to provide the addition agents in the form of a concentrate in a suitable oil, said oil containing rather high percentages of the addition agents. Such concentrates may be employed for further blending with a lubricating oil in the proportions desired for the particular conditions of use.

While mineral oil, generally, is the principal ingredient of the lubricant, it is not essential that it be the only ingredient other than the addition agents, provided that there be no additional ingredient which is incompatible with such addition agent, It is within the contemplation of this invention to include, if necessary or desirable, such other addition agents as are commonly added to improve the viscosity index or cold test of the lubricants; addition agents which function as corrosion inhibitors; as well as addition agents whose property is to reduce the tendency of the composition toward oxidation: and a lubricating composition accordin to this invention which also has a separate film-strength or oiliness increasing agent has been found to be especially effective.

When used in conjunction with a hydrocarbon lubricating oil, it is obvious that, generally, only such amounts of the addition agent may be included as are soluble in the specified amout of oil. By the term soluble," as herein used, it is intended to indicate the ability to form not only true solutions but also any form of substantially permanently homogeneous composition when incorporated in mineral 011. With most of the compounds there is usually little difllculty, especially if the incorporation is effected in the manner described in Cornell Patent No. 2,042,880, and since quitesmall percentages often give remarkably improved results, it is seldom of extreme importance that the addition agents be oil-soluble in all proportions.

The addition agents above enumerated for use in my compounded lubricants include certain ones which may be found to at least partially decompose under conditions of extreme stress such as the very high temperature encountered in certain classes of use, while others are quite stable even under such extreme'conditions.

The use for which the lubricant is designed therefore determines the particular type of addition agent to be selected. A certain amount of decomposition, which proceeds at a relatively slow rate, is usually not harmful. Care should be exercised, however, to select'for a particular set of operating conditions, an addition agent which in the oil base used,'will not decompose under such operating conditions except at a low rate.

By the term stable as used herein in describing the addition agents is meant thecharacteristic of the addition agents which enables them to resist decomposition in the oil under the conditon of .use for which the lubricating composition is designed.

The lubricating compositions of this invention may be prepared by first preparing the salt and then dissolving the salt in the oil base, or they may be prepared by reacting the acid in solution in all or a portion of the oil with a suitable basic compound in order to form the desired salt directly in solution in oil. In the lat ter case, it is frequently desirable to remove the water formed by the reaction, or which may have been added with the basic compound, by some means such as by heating at atmospheric or sub-atmospheric pressure.

In case the salt to be used is water-insoluble, an alternative procedure is as follows:

An aqueous solution of a water-soluble salt of the acid is first prepared, for example by dissolving the acid in an aqueous solution of caustic soda or caustic potash. The aqueous salt solution is then emulsified with oil and a water soluble salt containing the cation of the desired salt is added to the mixture. The desired salt is thus precipitated from the aqueous medium and subsequently or simultaneously dissolved by the oil medium. separation of the aqueous and oil layers is then effected for example by settling or centrifuging. Subsequent water-washing of the oil solution to remove traces of inorganic salts may be desirable, and removal of moisture may also be required.

A preferred class of addition agents for use in improved lubricating compositions of my invention may be defined as salts of aromatic acids, which salts contain the radicle CX--M in which X is an-element of the class consisting of oxygen and sulphur and M is a member of the class consisting of metals and basic radicles.

This application is a continuation-in-part of my aforesaid co-pending applications Serial Numbers 737,070, 245,226 now Patent No. 2,223,127, 332,782 now Patent No. 2,223,129, 332,781 now Patent No- 2,223,128, 334,082 now Patent No. 2,223,130, and 216,153, the latter being in turn a continuatiomin-part of Serial No. 760,038 now Patent No. 2,121,825. v Other modes of applying the'principle of the invention may be employed, change being made as regards the details described, provided the features stated inany of the following claims or the equivalent of such be employed.

I, therefore, particularly point out and distinctly claim as my invention:

1. A liquid lubricating composition comprising a major proportion of mineral lubricating oil and an oil-soluble salt of an aromatic acid in an effective amount insuflici'ent, however, to substantially change the viscosity of thecomposition.

2. A liquid lubricating composition comprising a major proportion of mineral lubricating oil and an oil-soluble salt of an aromatic acid in an amount from .10% to less than that which would substantially change the viscosity of the com position. I

3. A liquid lubricating composition suitable for use as the lubricant for the crankcase of internal combustion engines comprising a major proportion'of highly refined mineral lubricating oil to which has been added an effective minor amount of an oil-soluble salt of an aromatic acid without any substantial change in the viscosity of the refined mineral lubricating oil.

4. The method of reducing the rate of deposit in internal combustion engines of those materials usually resulting from the use of highly refined mineral lubricating oil as the primary lubricant which consists in incorporating in such lubricant a minor amount of an oil-soluble salt of an aromatic acid.

5. The method of reducing the rate of deposit on the pistons in internal combustion engines of those materials usually resulting from the" use under high temperatures of highly refined mineral lubricating oils as the primary lubricants,

' which consists in introducing to the area where such deposits tend to occur, a minor amount of an oil-soluble salt of an aromatic acid.

6. A liquid lubricating composition comprising a major proportion of mineral lubricating oil and a minor amount of an oil-soluble polyvalent metallic salt of an aromatic acid.

7. A lubricating composition comprising a major proportion of mineral lubricating oil and a minor proportion of an oil-soluble salt of an aromatic acid of the class having a carboxyl group attached to the ring.

8. A lubricating composition comprising a major proportion of mineral lubricating oil and a minor proportion of an oil-soluble salt of a substituted benzoic acid.

9. A lubricating composition comprising a major proportion of mineral lubricating oil and a minor proportion of an oil-soluble salt of a substituted salicylic acid.

10. A lubricating composition comprising a major proportion of mineral lubricating oil and a minor proportion of an oil-soluble salt of an arcmatic substituted carboxylic acid.

11. A lubricating composition comprising a major proportion of mineral lubricating oil and a minor proportion of an oil-soluble salt of an aromatic acid of the class consisting of sulphurcontaining aromatic-substituted aliphatic acids.

12. A lubricating composition comprising a major proportion of mineral lubricating oil and a minor proportion of an oil-soluble salt of an aromatic acid of the class consisting of hydroxyl containing derivatives of triphenyl methane.

1'3. A lubricating composition comprising a major proportion of mineral lubricating oil and a minor proportion of an oil-soluble salt of an aromatic acid having a molecular composition like that produced by condensing an aromatic heterocyclic compound with an aliphatic acid.

14. A lubricating composition comprising a, ma-

jor proportion of mineral lubricating oil and a A minor proportion of an oil-soluble salt of an arcmatic acid having a molecular composition like that produced by condensing an aromatic acid with an unsaturated halogen bearing aliphatic compound.

1'7. A lubricating composition comprising a major proportion of mineral lubricating oil and a minor proportion of an oil-soluble salt of an aliphatic substituted aromatic acid in which the aliphatic substituent contains oxygen.

18. A lubricating composition comprising a major proportion of mineral lubricating oil, and a minor proportion of an oil-soluble salt of an arcmatic acid having a molecular structure like that produced by condensing a salicyclic acid with oleyl alcohol.

19. A lubricating composition comprising a major proportion of mineral lubricating oil, and a minor proportion of an oil-soluble polyvalent metallic salt of an aromatic acid having a molecular structure like that produced by condensing salicylic acid with oleyl alcohol.

20. A lubricating composition comprising a major proportion of mineral lubricating oil, and a minor proportion of an oil-soluble salt of an arcmatic acid having a molecular structure like that produced by condensing an oxygen bearing aromatic derivative of furan with an aliphatic acid.

21. A liquid lubricating composition comprising a major proportion of mineral lubricating oil, and a minor amount of an oil-soluble metallic salt of an aromatic acid.

CARL F. PRUTTON. 

